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arXiv · 2105.04467

Magnon diffuse scattering in scanning transmission electron microscopy

Keenan Lyon·Anders Bergman·Paul Zeiger·Demie Kepaptsoglou·Quentin M. Ramasse·Juan Carlos Idrobo·Ján Rusz
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Abstract

We present a theory and a simulation of thermal diffuse scattering due to the excitation of magnons in scanning transmission electron microscopy. The calculations indicate that magnons can present atomic contrast when detected by electron energy-loss spectroscopy using atomic-size electron beams. The results presented here indicate that the intensity of the magnon diffuse scattering in bcc iron at 300~K is 4 orders of magnitude weaker than the intensity of thermal diffuse scattering arising from atomic vibrations. In an energy range where the phonon and magnon dispersions do not overlap, a monochromated scanning transmission electron microscope equipped with direct electron detectors for spectroscopy is expected to resolve the magnon spectral signatures.

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Keenan Lyon, Anders Bergman, Paul Zeiger, Demie Kepaptsoglou, Quentin M. Ramasse, Juan Carlos Idrobo, Ján Rusz. 2021-05-10. Magnon diffuse scattering in scanning transmission electron microscopy. https://doi.org/10.1103/physrevb.104.214418

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